1. Field of the Invention
The invention relates to an image processing device and an image processing method and, more particularly, to an image processing device and an image processing method capable of implementing bitstream stitching technique after interrupting image processing process.
2. Description of the Prior Art
Since some digital still cameras have smaller pixels, such as 3 million or 5 million pixels, than others, their processing time is shorter and can be accepted by users. However, when an image with larger pixels is encoded, it will spend a lot of time for encoding the whole image. If a user wants to display a currently captured image, which has not been encoded completely yet, the decoding process of the currently captured image can only be performed after the encoding process of the currently captured image has been completed. If the currently captured image is displayed after being encoded completely for a long time, the user will dislike waiting on the encoding process and have worse user experience. Therefore, the solution of the prior art is to generate and display a small image in advance and then encode the whole image behind the background gradually.
However, if the user wants to compare the currently captured image with the previously captured image in time, so far the solution of the prior art still has to encode the whole currently captured image first and the previously captured image can be then decoded and displayed. Accordingly, the delay of the processing time still cannot be solved.
In the prior art, one method for solving the aforesaid problems is to drop the encoded parts of the currently captured image and decode the previously captured image first, such that the user will not feel the delay while the previously captured image is requested to be displayed. However, the drawback of the method is that the encoded parts have to be dropped completely from the memory card and then the currently captured image has to be re-encoded again after decoding the previously captured image. If the user wants to display another image continuously, the encoding process of the currently captured image will not be finished consequently. Furthermore, it may not be easy to drop all of the encoded parts and it consumes lots of power and calculation resource.